Question

50 students passed in English 60 students passed in maths 40 students passed in both of them. find the total students​

Answer 1

Let U be the set of students who appeared for the exam,  

E be the set of students who passed in English and  

M be the set of students who passed in Maths.  

∴ n(E) = 50, n(M) = 60,  

40 students passed in both the subjects  

∴ n(M ∩ E) = 40  

Since, none of the students failed in both subjects  

∴ Total students = n(E ∪M)  

= n(E) + n(M) – n(E ∩ M)  

= 50 + 60 – 40 = 70  

∴ The number of students who passed at least in one of the subjects is 70.